1. Field of the Invention
The present invention relates to a printer with a cutter capable of appropriately cutting a recording sheet pulled out of a paper roll after performing printing on the recording sheet.
2. Description of the Related Art
In recent years, a number of various kinds of thermal printers have been provided which perform printing by pressing a thermal head against a special recording sheet (heat-sensitive sheet) that develops color when applying heat to the sheet. In particular, the thermal printers enable smooth character printing and colorful graphic printing without using toner, ink, etc., and hence the thermal printers are used preferably for printing of various labels, sales checks, tickets, and the like.
As typified by the thermal printers, a number of printers with a cutter having a cutter mechanism for cutting a printed recording sheet are known. The cutter mechanism generally includes a fixed blade and a movable blade capable of being slid with respect to the fixed blade. In particular, the movable blade is slid so as to ride on the fixed blade. Thus, the cutter mechanism can cut the recording sheet while sandwiching the recording sheet between both the blades like scissors.
Incidentally, as a structure in which the cutter mechanism of this type is incorporated into a printer, an integral type structure and a separation type structure are known. Specifically, in the integral type structure, a cutter unit including a movable blade and a fixed blade integrated with each other is incorporated to a main unit. In the separation type structure, a detachable unit is detachably provided to the main unit, and the fixed blade is incorporated into one of the main unit and the detachable unit and the movable blade is incorporated into the other of the main unit and the detachable unit. Thus, it is possible to separably combine the fixed blade and the movable blade with each other.
As disclosed in, for example, Japanese Patent Application Laid-open No. 2000-272200, as a printer provided with the separation type cutter mechanism, there is known a printer in which the movable blade is provided on the main unit side and the fixed blade is provided on the detachable unit side, and in which the detachable unit is capable of turning in a direction substantially orthogonal to a sliding direction of the movable blade.
Incidentally, in the printer with a cutter, there may arise various kinds of problems in that foreign matters get caught between the fixed blade and the movable blade, that the recording sheet gets caught (so-called paper jam), that blades bite each other during a cutting operation, and that the movable blade is stopped halfway through sliding due to malfunction or the like.
At this time, in the case of the cutter mechanism having the integral type structure, it is necessary to forcibly retreat the movable blade through manual manipulation of a releasing knob or the like for sliding the movable blade, to thereby separate the movable blade from the fixed blade. Therefore, an operation of restoring the movable blade requires time and effort, and hence a substantial burden is imposed on a user. In addition, when setting the recording sheet, it is necessary to pass the recording sheet through a gap between the movable blade and the fixed blade, and hence workability is poor.
In contrast, in the printer described in Japanese Patent Application Laid-open No. 2000-272200, the detachable unit is allowed to be separated from the main unit, and hence the printer is excellent in workability when setting the recording sheet. However, in the case where the movable blade is stopped halfway due to paper jam, or in the case where the movable blade is stopped halfway through sliding due to biting between the blades, the malfunction, or the like, the movable blade remains covering the fixed blade (riding on the fixed blade). Accordingly, even when it is intended to separate the detachable unit from the main unit through causing the detachable unit to turn in the direction substantially orthogonal to the sliding direction of the movable blade, it is difficult to separate the detachable unit from the main unit because the fixed blade is hindered by the movable blade. Therefore, similarly to the case of the above-mentioned integral type, it is necessary to manually and forcibly retreat the movable blade, and hence a substantial burden is imposed on a user.
In addition, even when the main unit and the detachable unit are separated from each other, the movable blade may slide accidentally, and hence the printer is in need of improvement in terms of safety.